1. Field of the Invention
The invention generally relates to attachments for wheeled implements, and more particularly to a single-wheeled draft attachment adapted to be coupled in a supported relationship with a wheeled implement, whereby vertical and lateral stability is imparted to the draft attachment by the wheeled implement as the implement is propelled by the draft attachment.
2. Description of the Prior Art
The prior art is, of course, replete with self-propelled machines, such as tractors, for towing agricultural implements. Included among such machines are tractors which utilize a plurality of wheels and parallel tracks for imparting vertical and lateral stability to the machines, particularly where the machines are controlled by a rider.
As can be appreciated by those familiar with the agricultural industry, tractors employed in towing implements such as balers, rakes, spray rigs and the like, substantial financial investments are required in order to initially purchase the tractor and, thereafter, substantial operational and maintenance costs are encountered. Of course, tractors often are characterized by a power potential far exceeding specified operational requirements, since a power potential must be built into the tractor which affords wide range of utility in order for the initial investment to be justified.
However, certain implements such as hay balers and the like, are equipped with power plants which function independently of the power plants provided for the tractors employed in towing the implements. As can be appreciated by those familiar with hay balers, and similar implements, a baler's packing ram is, in many instances, supported for rectilinear motion along a path paralleling the associated tractor's direction of travel. Consequently, oscillatory motion is induced in the implement which is, in turn, transmitted to the tractor through various couplings and drive linkages. Due to "slop" normally present in such couplings and linkages, the induced oscillatory motion tends to be amplified as it is transmitted to the towing tractor. This effect results in a cyclic loading of the towing tractor. Hence, the implement and the tractor, as well as its operator, are subjected to shock loads resulting in undesirable wear and severe fatigue as the tractor is cyclically loaded as a consequence of the reciprocation of the ram or similar device.
It has been suggested that a single wheel, self-propelling attachment be provided for drafting purposes in order to reduce financial investments and operational costs, while enhancing maneuverability of lightweight wheeled implements.
For example, U.S. Pat. No. 3,672,459 to Everett V. Rankins, which issued June 27, 1972, discloses an attachment for farm implements such as balers, rakes, spraying equipment, and the like. While the attachment disclosed and claimed in the patent serves satisfactorily for its intended purpose, it has been found desirable to provide an improved single wheel, self-propelling attachment having even greater utility and simplicity than that of the attachment disclosed in the aforementioned United States Letters Patent.
It is, therefore, the general purpose of the instant invention to provide a draft attachment for a wheeled vehicle which is of a simplified design, economic to fabricate and operate and is characterized by over-all improved maneuverability.